Sewage stabilizer



May 5, 1942. v e. HAWLEY SEWAGE STABILIZER Filed Sept. 17, 1937 4Sheets- Sheet 1 R O T N E V May 5, 1942. c. e. HAWLEY SEWAGE STABILIZER4 Shets-Sheet 2 Filed Sept. 17, 1957 INVENTOR May 5, 1942 c. a. HAWLEY2,232,225

SEWAGE STABILIZER Filed Sept. 17, 1937 4 Sheets-Sheet s INVENTOR Fllq. 5

4 Sheets-Sheet 4 000. 0000 Oetn oooaflo.

IO 80900. 0 O0 OOOOOQO' =INVENTOR c. G. HAWLEY SEWAGE STABILIZER FiledSept. 17, 1937 I May 5, 1942.

Patented May 1942 SEWAGE s'rannrzna Charles Gilbert Hawley, Chicago,111.; Hope Hawley Degenhardt and Virginia Taylor Hawley,

executrices of Charles Gilbert Hawley, de-

ceased, assignors, by mesne assignments, to

Hawley Engineering Corporation, Cleveland, Ohio, a corporation of OhioAmputation September 17, 1937, Serial No.164,367

1 Claim.

This invention has to do with liquids which tend to putrefy; adesignation which includes sewage and like organically polluted watersnot containing or supplied with enough oxygen to prevent putrefaction.

Two main objects are to be accomplished by the treatment of sewage; towit, the elimination of disease-producing bacteria to the extent demanded by' local health conditions; and the disposal of sewage withoutproducing nuisance or odor or endangering health.

In practice, the sewageis not destroyed nor is its complete purificationattempted. Instead, such wastes. in various states of purification. areultimately diffused in larger bodies of natural water, termed dilutingwater, in' expectation of final or at least adequatepurification'through if solids and seams are removed upon land theyshould be disposed of upon land and in manner the action of the oxygencontained by the di-' 7 luting water. Heretofore expected results haverarely been attained. The limitations of treating systems are recordedin failure to promptly separate scums and settleable solids and toprovide for adequate oxidation of colloidal and dissolved matters; andusually, pathogenic germs or organisms remain, makingterminal-chlorination a necessity.

In contrast, the demand is for a system of treatment capable ofproducing sewage which may be mixed with natural water to theadvantage'iof the latter and its banks and certainly without injury toaquatic organisms which ,are valuable for use and/or which normallyassist in water purification.

Clearly, procedure by dilution of raw sewage or of only partiallypurified sewage involves a depletion of oxygen not easy to replace, andit is obvious that it would be better if the diluting water were notcalled upon for assistance in sewage purification. Hence the constanteffort to lessen the oxygen tax upon natural bodies of water; as byremoving settleable impurities before discharging sewage into dilutingwaters; and in some cases, by protracted aeration and an activepropagation of non-pathogenic organisms which aid in harmlessly reducingorganic impurities to stable forms; all such procedures serving tolessen the overall putrecibility of the sewage and its oxygen demandupon the diluting waters.

Present day practices more or less effectively condition sewage, inadvance of dilution, but in none is even approximately permanentstability attained and the best still ultimate in demands upon thediluting waters, usually failing-to proto avoid nuisance, odors andhealth dangers. Such removed matters being unstable, should not be mixedwith earth upon which foods are produced, but should beburned Next, theoxygen required for the ultimate disposal of sewage may be added andemployed long in advance of sewage discharge or at the moment of suchdischarge; and if adequate in amount, will serve to obviate theabstraction of oxygen from the diluting water. These are basicprinciples of the present invention.

A primary object of sewage treatment is to make the same non-putrecible;that is stable, and safe for admixture with natural bodies of water,which waters are valuable for the aquatic organisms supported thereby orfrom which supplies are drawn for domestic use. I

The discovery now to be reported is, that while the solubility of oxygenin water is ordinarily regarded as limited to a few parts permillion,varying with temperature, it is in fact possible, by operations about tobe described, to imprison in even very foul water enough air to providein advance for the firm stabilization thereof and thus afford ample timeand means for the chemical and/or the bio-chemical destructive.reduction of contained organic matters; thereby protecting any dilutingwater with which such aerated sewage is admixed; and if desired, evenincreasing its oxygen content. Obviously it may be difficult to prove ameasurable increase but for all practical purposes this statement issound. A great range of aeration is here provided and whether or not theprocess shall be carried through to completeness may be freelydetermined to accord with local sanitary conditions and economiccircumstances.

A further discovery hereof is that by a brief atomization of sewage andthe use of air in swift motion therethrough it is possible to' displaceand blowout of sewage, quantities of dissolved, imprisoned or entrainedgases, vapors and light 7 organic structures; which, if allowed toremain would militate against prompt and healthful disposal of themainload of organic matters. Next, by abruptly terminating such atomization(restoring the liquid to mass formation) it is possible to charge thepurged or air. scrubbed sewage withair in relatively large volume and inthe state of minute particlesorglobules'which the massed waterthereafterholds in relatively firm imprisonment, suspension or solution, and henceready for combination with therein adjacent organic matters. Theseconcurrently sequential operations effectively stabilizethe sewage; andcomprise the gist-of thepresentin vention. 5

The invention hereof comprehendsthe employment of these discoveries andoperations in specially invented apparatus (as hereinafter"-de-- scribedand claimed) wherein and whereby they sparkling and harmless, dependsmerelyuponthe timeand cost' rates at which sewage is treated hereunder,-In this regard. it istoberemarked that a turbidity due merely tothe'prcsence of, inorganic solids is unobjectionable; likewise turtangential air, entrance tuyres, topped by an imby imprisoning airtherein, prior to discharge from restraint. a

In practice, the aforesaid restricted passage for the -air and waterbestcomprises a so-called centrifugal tuyere or unit, closed atthe"bottom, open at the top, and characterized by'a plurality of perforatecylindrical section wherein occurs the described consolidation of liquidand imprisonment of air. ;,The description thus far has been limited tothe treatment of heavily polluted water. It is here pointed' out thatwater for human consumption may be likewise treatedand markedlyimproved,

" fromfthe standpointsof palatability, odor, sterility and protractedstability.

bidity due to minute'org'anic matters, sqlongas the latter'areaccompanied by adequate/oxygen ashere described.

A very important-functionofthe operations described residesin thedisengagement of oils and soapy and fatty matters, permitting them to"be easily skimmedfrom the sewage stream,1prior'to dilution. Ordinarilysuch matters yield totreat ment very slowly and are difficult to getridof.

' It is important to note that the described pul veriz'a'tion of waterand air,'appears to explain the pronounced extermination of protozoa.and anaerobic and facultative bacteria, 'as observed'in this'opera'tion.Apparentlythe presence of ample oxygen and the swiftchange fromtensional im' prisonment within the water, to 'suddenfreedorn upon thesurfaces ofthe waterparti cles, has the effect of bursting or destroyingthe fragile cells ofprotozoa, and pathogenic bacteria On the other hand,"the more minute aerobic bacteria in considerable measure escapedestruction and may be discharged with the aeratedwate'r, thereafter toplay their proper'part'in water purification."

Another advantage hereinafter enlarged upon Both discovery and inventionwill be more clarly'understood upon reference to the accompanying.exemplary drawings and description, which explain the foregoing andother components of the invention.

In said drawings F g. 1 is a vertical cross section of.a sewagestabilizer embodying the present invention and diagrammaticallyillustrating the operation thereof under air suction conditions; Fig. 2is a horizontal section of a single centrifugal tuyere or unit, onth'eline 2-2 of Fig. .1; Fig. 3 is a horizontal section on the line 3-3of Fig. 1; Fig'. 4 is a verticalsectional view of a tuyre or unit ofslightly modified formand disclosing an ultra violet lamp which "may beused for the annihilation of bacteria exposed in the tuyre by theoperation described; Fig. 5 is like unto-Fig. 1 but illustrates theapparatus as modified for pressure air operation; Fig. 6 is adiagrammatic sectional elevation of a'sewa-ge treatment system ofnovei-design, more completely embodying the invention; and Fig.7 is aplan;

"* view-taken from 'Fig. 6.

The apparatus shown in Figs. 1, 2 and 300mprises the so-calledstabilizer of this invention. It is of a multiple type, beingcharacterized'by a plurality of centrifugal unitsor tuyres, marked 2,constructed and functioning as previouslydescribed. That is, each tuyereis of generally cylindrical form, with a closed bottom 3 and'animperforate cylindrical top'p'ortion 4, which parts are-joined by aplurality of tangential blades 5;

i the latter forming an equal number of slot-like relates to the use ofultra-violetrays for the complete annihilation of bacteria. As wellknown, the effect of the ultra-violet ray is limited virtually to thesurface upon which it impinges.

Under the present invention thesuperficialarea of the liquid istremendously increased and every particle is' directly exposed for' suchtreatment.

Speakingfurther of the present invention, it

*may be said to comprise-or include the purging and enforced aeration ofsewage and the like; and, in contrast with former methods of aeratingwater on masse,'it consists in performing the op;

erations in space and in 'a state of fine'pulverization within arestricted passage, immediately followed by consolidation of the liquid.

tangential tuyere openings -6. The, combined area of these openingsclosely approximates that of the open top of the tuyere. However, thiratio may be varied as required to suit differing-conditions. Thearrangement of blades and openings is clearly shown in Figs. 1 and 2.- IAs a guide to others, it is explained that the tuyres here shown are ofhalf 'normal size, actually.being 2% inches in diameter and 7- /2 inchestall. A

.The stabilizing effects reported were secured by using just suchtuyeres. Each such tuyere raisesand deliversfroma lower level 2 to 4gallons of sewage per minute, depending upon the rate at which air ispassed through the tuyre More specifically, the invention resides inemopenings. And importantly, in the case of the tu-yeres shown, theseliquid rates are indexed by respective pressure drops of 2 and .4 inchesof water; the difference between the pressure of air entering the tuyreand that of the air leav-' ing the same. Obviously little power is orneed be expended in performing the hereinbefore described purging andstabilizing operations.

Greater water deliveries for the same pressure drop may be secured bylessening the tuyre height; a statement which makes it clear thatfurther power may be conserved, provided other conditions permit a lessprotracted working of the liquid. Likewise with tuyres of any givendesign the power and delivery rates may be varied within wide range,always having. in view first costs and the efiects required. I

Notwithstanding these specifications of size and capacity it is to beunderstood that the invention is not limited thereto, for as indicatedthe stabilizer tuyres may partake of all the various dimensions andproportions best calculated to produce the results desired with minimumexpenditures of power.

The box or chamber 1 is provided for the reception of liquid and airfrom the tuyres 2. It has openings in its floor 8, wherein the upperends of said tuyres are fastened, leaving the parts 4 thereof standingabove the floor and thus converting the lower part of the box 1 into areservoir for the reception of the liquid received from the tuyres. I

As shown, the box I is relatively large in relation to the combineddischarge areas of the tuyeres and amply large to permit quicksettlement therein of theliberated liquid. Residual air, containinggases, and other matters purged from the liquid as before explained,passes oil through an opening or openings 9 at the top of the box.

The box floor 8 has other openings from which depend tubes or ducts I 0,through which the elevated and aerated liquid is discharged from thebox.

The apparatus of Fig. 1 operates under partial vacuum (preferablycreated by'a centrifugal fan F, as shown in Figs. 6 and '7) and for themaintenance thereof air should be prevented from entering through thedrain tubes [0. Hence, as shown, the lower ends of those tubes aresubmerged or sealed in liquid, the latter being held As shown in Figs. 6and 7, a stabilizer may be arranged at the reception end of as'edimentation tank T or may be arranged at the outfall end Y ofthat'tank, as also thereshown, or both arrangements may be employed. Inthe first named position, the pan ll receives sewage from a sewagescreen ii. For furtheninformation concerning-said screen, reference maybe made to applicant's prior application S. N. 120,792, filed January15, 1937.

Through the use of a fine screen the sewage which reaches the tuyres 2of the stabilizer is freed from particles large enough to clog thosetuyeres, and the sewage passing through the tuyeres is uniformlyatomized, purged and aerated and is then discharged into the crosstrough H, in or at the reception end of the tank T.

The cross trough ll here functions as a distributor, assuring an evenfeed of sewage throughout the cross section of the tank T. Upon leavingthe cross trough, the scums readily separate By the action of thestabilizer, as before described, the raw sewage is dependably stabilizedand cannot become septic. In consequence, even the settled sludgeremains fresh, and the process thus affording absolute assurance againstre-contamination of the sewage.

in a cross trough II, into which the tubes discharge the liquid from thebox I. The aerated liquid leaves that trough over an outfall weir l3,and passes onward toward dilution, as by way of an outfall duct l2.

In order that liquid may enter the tuyres to be atomized and elevated,as described, it is necessary that it shall be supplied to the lowerparts thereof and therefore arrangements are made to flood said lowerparts to a level slightly above the tuyere bottoms 3; and to keep thatlevel substantially constant, though it admits of considerablevariation.

To such ends, the box and tuyeres are suitably supported in a manner toallow the lower ends of the tuyeres to dip beneath the surface of thestream of sewage or other liquid to be so treated. The space betweensaid surface and the box is open, so that air may freely enter thetuyeres through the many tangential tuyre openings thereof.

Obviously, the stabilizer may be thus positioned in and above any partof a sewage stream. But as these stabilizers are usually associated withsedimentation tanks, such as the tank T, shown in Figs. 6 and '7, it isbest to prevent tank dis-. turbances by the swift entrance of air andliquid into the tuyeres; and most conveniently, the stream is formed andmaintained in a shallow pan 14, really a shallow duct, arranged beneaththe tuyeres 2. The liquid is taken from the pan I4 and atomized asrapidly as it reaches the tuyeres. Any suitable means may be. employedto provide and control the admission of liquid to this feed pan ortrough I4.

The settled solids accumulate in the bottom of the tank, which latterhas the form of a trough, and are immediately, though slowly, dischargedtherefrom by the action of an endless drag chain It, which operates todeposit the solids in the sludge pocket [1, the lower part of which isin open communication with the bodyof the tank. This quick removal ofsludge also insures against re-contamination of the slowly clarifyingsewage, as mentioned in aforesaid application.

Because of the small size of the solids passed by the screen l5, thesludge settles densely and,

' accompanied by less water than usual, is readily disposed of in adesiccating incinerator DI; as is true also of the screenings taken fromthe screen. Details concerning such parts and operations are alsoavailable in aforesaid earlier application.

'Hereunder, special advantage is taken of the incinerator DI. Whateverits form, an incinerator includes a furnace and requires air to sustaincombustion therein. When raw sewage is screened, purged and aerated asherein described, the exhausted air is likely to contain odorousconstituents. If exhausted into the atmosphere these may at times beobjectionable. As a definite preventative and to conserve the wholevalue of the exhausted air, this invention comprehends the employment ofsuch polluted air in the incinerator, as represented by the piping 9',which leads from the top of the separator box I to the fan F, and thenceinto the lower part of the incinerator. A desirable closed cycle is thusprovided and, as the incinerator DI operates without creatapplication,and discharges the scum and a small quantity-of water through an outfallpipe l9,

thence to be gravity-separated and disposed of.

' Progressively, the clarified sewage passes be neath and rises behind across baflie l8 'and, as here shown, passes into a stabilizer 'pan l4,

through an upflow space 20." l

/ Referring again to-Fig. I, which illustrates a stabilizer for theoutfallend" or the tank, it will be seen that the weir strip 14',marking one end of the pan |4,'governs the normal height WL of theliquid ina tank T, and the partially, purified liquid falls over thatstrip I4 and into the pan i4, thence to be pumped or abstracted by theaction of the air in stabilizer tuyeres.

r l I 'aaaaaza,

" The tank level WL varieswith the volume of sewage delivered to thetank and this variation may be so considerable as to occasion'anoverloading of the stabilizer .tuyre unless the velocity of the air iscorrespondingly increased. Therefore, it is-thought best to governthemaximum height to'which liquid may-rise in the pan l4, and this is doneby providing the pan with an end 7 strip 2| which is higher than thestrip l4, and

overwhicl on occasion, sewage may by-pass into the outfall trough H. v

-At this point let it be said that the present invention comprehends theregulation of the air flow\ through the describedvtuyeres in order" thatpower shall be expended only in proportion to the strength and volume ofthe raw sewage which enters the system. This is done'as follows.

As stated in aforesaid application, the speed and capacity of therotary' screen l5 are here automatically regulated by'a mechanism whichis controlled by the rise and fall of a float restingin the raw. sewageapproaching the screen.' In Fig. 6 this float is marked The requirementsof the present invention'are satisfied by 'a'connection (electrical ormechanical) between that -tation tank. This :,is explained by theforcible water is purged and charged or re-charged' with fresh air.

Arriving at the top of the imperforate part 4, the water whirls from theupper edge thereof and falls into the lower part of the air box orseparatorl, hence to pass outward through the I openings that lead fromthe bottom of the air box.

'It is notable that the tuyres illustrated are of a length or heightthatexceedsthe air pressure difierence between the bladed exterior and thetop of the tuyere. is made to rise through the tuyere. This is explainedby the fact that the superficial area, the sail area, of the liquid ishere tremendously in creased and the polluted water is easily sweptupward by the moving air. In turn this explains the small consumption ofpower.

Another noticeable fact concerning this process is this: The colloidalmatters contained by sewage are observed to be, in considerable measure,brought together or aggregated with one another and with larger sewageparticles; and therefore settle-more promptly in the sedimenscrubbingtogether of the'particles, as a part of the described centrifugalbehavior of the air and water in the tuyeres hereof, particularly thoseor I small diameter.

float. and the regulator ,of the air moving motor which belongs to oneor both of the described stabilizers. It is deemed unnecessary to hereinbetter illustrate the .complete regulating. means.

The operation of the stabilizer tuyeres is well depicted byFigs. 1 and 2and particularly byjthe many dots 22 and by arrows 23 and 24. As bestshown in Fig.2, the air which forcibly entersthe tangential tuyeres 6takes on a rapid whirling motion within the tuyere, as represented byarrows 24. Liquid entering through the lower parts ofthe tuyeres 6encounters the whirling air and is thereby immediately swept intorotation and disturbed and broken upv to such an extent as to be finelyatomized or pulverized, and in that state it progresses spirally to theimperforate top 40f the tuyere.

At that point the rapidly whirling pulverized liquid inwardly displacedby the entering airand. outward propelled centrifugal action is formedinto a hollow cylindrical body, inwardly offset from the interior of thetuyere blades 5 and whirlinglymaintained in space. spiralling upwardunder the upward impulsion of theair, the liquid arrives at the top ofthe tuyere, and by centrifu gal force is thrown outward against theimperforate part 4 and forcibly massed thereon.

Obviously, the air which enters the tuyre has only one avenue of escapeand that is, through a foraminous wall of water, which the whirling airserves to maintain. It is equally apparent that in It is-belleved thatthe principles, operations and the mechanical details paramount in thisinvention will now be thoroughly understood, and few modifications andqualifications thereof remain to be described.

The invention is not limited to the operation of this stabilizer underpartial vacuum but is readily adapted for operation under positivepressure. Further, when so operated, the stabilizer is given thecapacity of being able to discharge the aerated water at a higher levelthan that at which it receives the polluted water.

This pressure operation is accomplished as shown in Fig. 5, wherein anair pressure box 25, is prov vided beneath the separator box Ia andcontains the tuyeres 2a. The box 25 receives air under slight pressurethrough a duct 26,,the air whirling upward, through the centrifugaltuyeres and exhausting through the box "la'.

It will be noticed that the bottom of the pres-' sure box25 is closed,except that it contains openings in which the lower'ends of the tuyerestructures are fastened: 'The lower part of the pressure box issubmerged in the liquid L, and the liquid enters the tuyeres 2a throughcentral holes 222, provided in the bottoms 3b thereof.

centrifugally created suction may be depended upon to lift or pumpliquid into the tuyeres through these openings but it is unnecessary toexpend power for that purpose, when it is so much easier to partlysubmerge the pressure box andjthus ensure adequate liquid feed throughthe bottoms of the tuyeres.

passing through that whirling wall, the air is V finely subdividedthereinand not only scrubs but also thoroughly impregnates the particlesof water and is made ready for the described imprisonment in the liquidwhen the water is cornpacted against the imperforate cylindrical surface4., Thus in continuous operation, the polluted The aerated water isdischarged through a slot or port lb, at the bottom of the separator la,and is carried away bya duct in. So far as the essential operation isconcerned, the appa- Yet a large volume of liquid opening presents alevel lower edge an emergency outfall weir 28'. V

Fig. 4 illustrates a tuyere much like those shown in Figs. 1, 2 and 5,but of less height, and also having an imperforate cylindrical portion4a, which is of less diameter than the body of the tuyre. In such topconstruction an over-- hanging shoulder 29 is provided between thetuyere openings and the part 4a, and serves to arbitrarily increase thethickness .of the foram inous wall formed by the air sustained whirlingparticles of water within the tuyere.

Fig. 4 also depicts an ultra-violet lamp 30, which is installed axiallywithin the tuyre and is there operated to annihilate bacteria that areexposed in the manner before described.

The importance of the present invention is well illustrated or explainedby the results thus far obtained. Raw sewage, merely screened, has beenoperated upon as herein described and, though carrying a heavy burden ofputrecible matter, has remained stable for fully ten days; a period muchlonger than ever before reported; and most remarkable when it isrealized that such stability was imparted in so brief a time of passage,little if any more than one second. The same sewage, when diluted, hasremained stable for much longer periods and likewise sewage which hadbeen settled or prepurified.

Furthermore, in these cases the solids have been so far maintained in orrestored to a healthful state that they have been avidly eaten by fishwith no apparent injury to the fish; and delicate water plants immersedin quantities of thus aerated sewage thrive much as though submerged inpotable water.

It isto be noted that the whole process is congulcted in open air and atatmospheric tempera- As will be apparent, the output of the aerator,here employed at the outlet of a primary sedimentation tank, may bedirected into a secondary sedimentation tank for further clarification.Such secondary tank should be provided with which forms means forremoving setled sludge; whatever its nature; as in the casev of thetank.

Hereinunder the simplest sewage disposal system will consist inscreening raw sewage (screenings to be later disposed of) and thenpurging and aerating the sewage as here described, to condition it fordilution. r

A better system will provide for screening the sewage, forsedimentation, and removal of scums and sludges, followed by thedescribed purging and aerating operation.

A still better system may introduce aeration immediately after thescreening of the raw sewage to allow of protracted sedimentation withoutfear of putrefaction and with assurance of obtaining fresh sludge.

A complete system hereunder will comprise a screening, purging andaerating operation; sedimentation: removal of sludges and scum; theutilization or destruction of both; the re-aeration of the thus purifiedsewage, and the sedimentaion of the re-aerated sewage in advance of itsdilution.

Because the herein described stabilizing apparatus may be employed inarts other than the treatment of sewage, it is herein claimed as astructure capable of such other uses.

In the foregoing discussion of the treatment of sewage, emphasis hasbeen laid upon the importance of the oxygen which is derivable from air.The nitrogen of air has been virtually disregarded because its part inthe chemistry involved is not well defined. Nevertheless, it may befound to play an important part in the stabilization of sewage, eitherat the instant of application, or at a later time.

I claim:

subjecting liquid sewage in an atomized state to a whirling current ofair in a confined space and resolving the atomized liquid while stillconfined into a mass under the influence of said current of air.

CHARLES GILBERT HAWLEY.

described primary

